Camshaft adjusters are industrial modules for adjusting the phase angle between a crankshaft and a camshaft in an internal combustion engine.
A camshaft adjuster of the type mentioned at the outset is also known from DE 10 2008 011 116 A1. The separating sleeve inserted into the hub separates the supply paths for hydraulic fluid for the first and second supply channels through the camshaft by forming at least one first and one second axial supply space. The supply spaces are supplied with hydraulic fluid via radial bores situated outside the rotor in the camshaft. For this purpose, a rotary transmitter is provided, which switchably allows the hydraulic fluid to flow in and out of the radial bores of the rotating camshaft with the aid of annular chambers. The separated axial supply spaces of the separating sleeve couple the supply channels of the rotor through the camshaft to the external hydraulic fluid supply. The first and second supply channels of the rotor are connected to the particular pressure chambers of the camshaft adjuster. For example, a retard of the rotor with respect to the stator, and thus the camshaft with respect to the crankshaft, takes place by applying pressure to the first supply channels, and an advance takes place by applying pressure to the second supply channels.
The separating sleeve according to DE 10 2008 011 116 A1 has a double-walled design for the purpose of forming the separated axial supply spaces. The receiving bores in the camshaft and in the hub of the rotor are each designed as complex stepped bores, which require complex manufacturing. The axial supply spaces designed as annular chambers and the corresponding recesses needed for coupling in the rotor result in a relatively large dead volume, which must be flowed through during activation of the pressure chambers.